PREFACE:
X3J13 voted in January 1989
(LOOP-FACILITY)
to adopt an extended definition of the loop macro
as a part of the forthcoming draft Common Lisp standard.

This chapter presents the bulk of the Common Lisp
Loop Facility proposal, written by Jon L White. I have
edited it only very lightly
to conform to the overall style of this book and have inserted a small
number of bracketed remarks, identified by the initials GLS.
(See the Acknowledgments to this second edition for
acknowledgments to others who contributed to the Loop Facility proposal.)